<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <script>

    let map = new Map();
    map.set('11', true)
    map.set('12', "你好世界");
    map.set('11', "天气不错")
    // map.delete('11')
    var x = map.get('12')
    console.log(x);
    x = map.keys()
    console.log(x);
    x = map.values()
    console.log(x);
    map.entries().forEach((v, i) => {
      console.log(v[0], v[1], i);
    })





    // map.clear()
    console.log(map);
    console.log(map.size);



  </script>
</body>

</html>